Functional group patterns 336 INDEX

Theoretical models provide interesting alternatives to evaluate intrinsic electronic substituent effects. This can be done for instance by means of the response functions defined as global or local reactivity indices. The variations of a reactivity index for a set of functional groups attached to a common molecular frame may also be taken as a measure of the influence that the different substituents may have on the reactivity pattern of molecules. 

In summary, the calculated electrophilicity index, to, for a series of substituted ethylenes may be used to make reliable estimates of the intrinsic electronic contributions to the <7p constants of Hammett equation for a series including 42 functional groups commonly present in organic compounds. The computed trjto) parameters account for the intrinsic electronic substituent effects, which are contained in the experimental values of the <7p substituent constants. This useful predictive tool to assess the reactivity pattern of gas-phase reactions or those reactions that take place in solvents of very low polarity. 

It is also interesting to examine the effect that the electron-releasing groups may have on the local electrophilicity pattern in ethylene 29. These systems have some importance in the IED processes. Consider for instance the electron-rich ethylenes 33 and 35. On the basis of the Fukui function alone, methyl vinyl ether 33 shows nucleophilic activation at the C2 carbon, fk = 0.470. Dimethylvinylamine 35, on the other hand, displays a similar local reactivity pattern, fk = 0.411. Note that on the basis of the to index, both compounds are predicted as marginally electrophilic. Both compounds 33 and 35 are... 

Additional physical evidence supporting the development of congestion as a function of generation is shown in the composite comparison of dendrimer nano-periodic property patterns as illustrated in Sect. 6.5.2. Plots of intrinsic viscosity [ /] [9, 113], density z, stuface area per Z group (AJ, and refractive index n as a function of generation clearly show maxima or minima at G = 3-5, paralleling computer-assisted molecular-simulation predictions [84, 114], as well as extensive photochemical probe experiments reported by Turro and coworkers [105-108]. 

However, in order to reduce the EMG features to the smallest dimension feature vector, we can remove features that have the same pattern that we can observe that from the scatter plots. In more details, in case of time domain features that are calculated based on their amplitudes, we found that features in the secondary group have the same pattern. Thus only the best one in this group is recommended that is the WL feature with 128-ms window size function. In addition, for the time domain features that obtained the frequency information, WAMP has the better in cluster separability than ZC and SSC. The optimal threshold value of WAMP is about 25 mV and the optimal threshold value of ZC and SSC is 5 and 2 mV, respectively. Furthermore, the modified version of the MAV is worse than its traditional version. The whole features in frequency domain show poor class separability. The MDF obtains the larger RES index than the MNF. Nevertheless, the MAVS is the worst classifier performance compared to the other features. Its... 

---